That makes it one of the easier methods to setup and uses a private tunnel. There are two free services that are very similar to each other that allow you to have your very own private VPN service.  They do a nice trick which is key to this working. Your server which is "stuck" behind the CGNAT makes an outgoing "ping" to their service every once in a while while keeping a socket open to their server.  Since your server opened the communication it pushed through the block and now can allow tra